schwoates
Member
Hello everyone,
Getting ready to upgrade a PLC-5 system to ControlLogix for a client and there is an existing 1771-DS Latching input card used. It is used in paired mode with two photo-eye's detecting an inverted aluminum can. 1 PE is looking at the side of the can to create a Gate and the other PE is looking from above to detect the bottom of the can for the Pulse. If the can is inverted (can opening facing up towards the PE) during the gate, the PE will pulse and the input will latch to keep the filler from trying to fill an inverted can.
The general consensus is that the 1771-DS is being used because of input delay time during the days when the PLC-5 was the best out. I'm wondering what the best option for 1756 would be to replace this. So far I've come up with using a 1756-IB16IF and simply latching a fault bit in the controller if both inputs are on at the same time. Seems easiest and the 14 us nominal Off to On delay seems mighty quick if you ask me. I've also read about the 1756-IB16ISOE. I'm wondering if this is something I should even bother with or if the 1756-IB16IF will be plenty sufficient.
Thanks for the input!
Getting ready to upgrade a PLC-5 system to ControlLogix for a client and there is an existing 1771-DS Latching input card used. It is used in paired mode with two photo-eye's detecting an inverted aluminum can. 1 PE is looking at the side of the can to create a Gate and the other PE is looking from above to detect the bottom of the can for the Pulse. If the can is inverted (can opening facing up towards the PE) during the gate, the PE will pulse and the input will latch to keep the filler from trying to fill an inverted can.
The general consensus is that the 1771-DS is being used because of input delay time during the days when the PLC-5 was the best out. I'm wondering what the best option for 1756 would be to replace this. So far I've come up with using a 1756-IB16IF and simply latching a fault bit in the controller if both inputs are on at the same time. Seems easiest and the 14 us nominal Off to On delay seems mighty quick if you ask me. I've also read about the 1756-IB16ISOE. I'm wondering if this is something I should even bother with or if the 1756-IB16IF will be plenty sufficient.
Thanks for the input!